/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.log4j.spi;

import java.io.IOException;
import java.io.LineNumberReader;
import java.io.PrintWriter;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.ArrayList;

/**
 * ThrowableInformation is log4j's internal representation of throwables. It
 * essentially consists of a string array, called 'rep', where the first
 * element, that is rep[0], represents the string representation of the
 * throwable (i.e. the value you get when you do throwable.toString()) and
 * subsequent elements correspond the stack trace with the top most entry of the
 * stack corresponding to the second entry of the 'rep' array that is rep[1].
 * 
 * @author Ceki G&uuml;lc&uuml;
 * 
 * */
public class ThrowableInformation implements java.io.Serializable {

	static final long serialVersionUID = -4748765566864322735L;

	private transient Throwable throwable;
	private String[] rep;

	public ThrowableInformation(Throwable throwable) {
		this.throwable = throwable;
	}

	/**
	 * Create new instance.
	 * 
	 * @since 1.2.15
	 * @param r
	 *            String representation of throwable.
	 */
	public ThrowableInformation(final String[] r) {
		if (r != null) {
			rep = (String[]) r.clone();
		}
	}

	public Throwable getThrowable() {
		return throwable;
	}

	public String[] getThrowableStrRep() {
		if (rep != null) {
			return (String[]) rep.clone();
		} else {
			StringWriter sw = new StringWriter();
			PrintWriter pw = new PrintWriter(sw);
			throwable.printStackTrace(pw);
			pw.flush();
			LineNumberReader reader = new LineNumberReader(new StringReader(sw
					.toString()));
			ArrayList lines = new ArrayList();
			try {
				String line = reader.readLine();
				while (line != null) {
					lines.add(line);
					line = reader.readLine();
				}
			} catch (IOException ex) {
				lines.add(ex.toString());
			}
			rep = new String[lines.size()];
			lines.toArray(rep);
		}
		return rep;
	}
}
